Dynamical Control of Orbital Ordering and Ferroelectric-Induced Polar State in Metallic Manganites

Here, we report an exquisite strategy that the B12 enzymes exploit to manipulate the reactivity of their radical intermediate (Adenosyl radical). Based on the quantum-mechanic calculations, these enzymes utilize a little known long-ranged through space quantum Coulombic effect (QCE). The QCE causes the radical to acquire an electronic structure that contradicts the Aufbau Principle: The singly-occupied molecular orbital (SOMO) is no longer the highest-occupied molecular orbital (HOMO) and the radical is unable to react with neighbouring substrates. The dynamic nature of the enzyme and its structure is expected to be such that the reactivity of the radical is not restored until it is moved into close proximity of the target substrate. We found that the hydrogen bonding interaction between the nearby conserved glutamate residue and the ribose ring of Adenosyl radical plays a crucial role in manipulating the orbital ordering

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Radical Enzymes Control the Chemistry of Their Highly Reactive Intermediates Using the Quantum Coulombic Effect

10.26434/chemrxiv.12839177 ◽

2020 ◽

Author(s):

Hossein Khalilian ◽

Gino A. DiLabio

Keyword(s):

Hydrogen Bonding ◽

Molecular Orbital ◽

Reactive Intermediates ◽

Hydrogen Bonding Interaction ◽

Orbital Ordering ◽

Dynamic Nature ◽

Radical Intermediate ◽

Highest Occupied Molecular Orbital ◽

Bonding Interaction ◽

Close Proximity

Here, we report an exquisite strategy that the B12 enzymes exploit to manipulate the reactivity of their radical intermediate (Adenosyl radical). Based on the quantum-mechanic calculations, these enzymes utilize a little known long-ranged through space quantum Coulombic effect (QCE). The QCE causes the radical to acquire an electronic structure that contradicts the Aufbau Principle: The singly-occupied molecular orbital (SOMO) is no longer the highest-occupied molecular orbital (HOMO) and the radical is unable to react with neighbouring substrates. The dynamic nature of the enzyme and its structure is expected to be such that the reactivity of the radical is not restored until it is moved into close proximity of the target substrate. We found that the hydrogen bonding interaction between the nearby conserved glutamate residue and the ribose ring of Adenosyl radical plays a crucial role in manipulating the orbital ordering

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Faculty Opinions recommendation of Transcriptional regulation of germinal center B and plasma cell fates by dynamical control of IRF4.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718018780.793478392 ◽

2013 ◽

Author(s):

Stephen Nutt

Keyword(s):

Transcriptional Regulation ◽

Plasma Cell ◽

Germinal Center ◽

Cell Fates ◽

Dynamical Control

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Enhanced energy storage properties at phase boundary in Fe‐doped Ba(Zr0.04Ti0.96)O3 ceramics with a slush polar state

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-021-05973-9 ◽

2021 ◽

Author(s):

Yu Fang ◽

Yucong Zhang ◽

Chen Wu ◽

Changyi Liu ◽

Wenwei Ge ◽

...

Keyword(s):

Energy Storage ◽

Phase Boundary ◽

Polar State ◽

Energy Storage Properties ◽

Storage Properties

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Imaging the formation and surface phase separation of the CE phase

npj Quantum Materials ◽

10.1038/s41535-021-00353-2 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Haibiao Zhou ◽

Qiyuan Feng ◽

Yubin Hou ◽

Masao Nakamura ◽

Yoshinori Tokura ◽

...

Keyword(s):

Magnetic Field ◽

Phase Transitions ◽

Charge Ordering ◽

Zero Magnetic Field ◽

Ferromagnetic Phase ◽

Emergent Properties ◽

Orbital Ordering ◽

Strong Electron ◽

Antiferromagnetic Correlation ◽

Ordering Transitions

AbstractThe CE phase is an extraordinary phase exhibiting the simultaneous spin, charge, and orbital ordering due to strong electron correlation. It is an ideal platform to investigate the role of the multiple orderings in the phase transitions and discover emergent properties. Here, we use a cryogenic high-field magnetic force microscope to image the phase transitions and properties of the CE phase in a Pr0.5Ca0.5MnO3 thin film. In a high magnetic field, we observed a clear suppression of magnetic susceptibility at the charge-ordering insulator transition temperature (TCOI), whereas, at the Néel temperature (TN), no significant change is observed. This observation favors the scenario of strong antiferromagnetic correlation developed below TCOI but raises questions about the Zener polaron paramagnetic phase picture. Besides, we discoverd a phase-separated surface state in the CE phase regime. Ferromagnetic phase domains residing at the surface already exist in zero magnetic field and show ultra-high magnetic anisotropy. Our results provide microscopic insights into the unconventional spin- and charge-ordering transitions and revealed essential attributes of the CE phase, highlighting unusual behaviors when multiple electronic orderings are involved.

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Dynamical control of the conductivity of an atomic Josephson junction

Physical Review Research ◽

10.1103/physrevresearch.3.013111 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Beilei Zhu ◽

Vijay Pal Singh ◽

Junichi Okamoto ◽

Ludwig Mathey

Keyword(s):

Josephson Junction ◽

Dynamical Control

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Reconfigurable artificial microswimmers with internal feedback

Nature Communications ◽

10.1038/s41467-021-25108-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

L. Alvarez ◽

M. A. Fernandez-Rodriguez ◽

A. Alegria ◽

S. Arrese-Igor ◽

K. Zhao ◽

...

Keyword(s):

Phase Transition ◽

Dielectric Properties ◽

Light Absorption ◽

Local Heating ◽

Volume Phase Transition ◽

Active Materials ◽

Colloidal Clusters ◽

Robotic Devices ◽

Dynamical Control ◽

Synthetic Models

AbstractSelf-propelling microparticles are often proposed as synthetic models for biological microswimmers, yet they lack the internally regulated adaptation of their biological counterparts. Conversely, adaptation can be encoded in larger-scale soft-robotic devices but remains elusive to transfer to the colloidal scale. Here, we create responsive microswimmers, powered by electro-hydrodynamic flows, which can adapt their motility via internal reconfiguration. Using sequential capillary assembly, we fabricate deterministic colloidal clusters comprising soft thermo-responsive microgels and light-absorbing particles. Light absorption induces preferential local heating and triggers the volume phase transition of the microgels, leading to an adaptation of the clusters’ motility, which is orthogonal to their propulsion scheme. We rationalize this response via the coupling between self-propulsion and variations of particle shape and dielectric properties upon heating. Harnessing such coupling allows for strategies to achieve local dynamical control with simple illumination patterns, revealing exciting opportunities for developing tactic active materials.

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Femtosecond control of phonon dynamics near a magnetic order critical point

Nature Communications ◽

10.1038/s41467-021-23059-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

O. Yu. Gorobtsov ◽

L. Ponet ◽

S. K. K. Patel ◽

N. Hua ◽

A. G. Shabalin ◽

...

Keyword(s):

Critical Point ◽

Landau Theory ◽

Density Wave ◽

Spin Density Wave ◽

Vibrational States ◽

Spin Order ◽

Lattice Displacement ◽

Far From Equilibrium ◽

Crystalline System ◽

Dynamical Control

AbstractThe spin-phonon interaction in spin density wave (SDW) systems often determines the free energy landscape that drives the evolution of the system. When a passing energy flux, such as photoexcitation, drives a crystalline system far from equilibrium, the resulting lattice displacement generates transient vibrational states. Manipulating intermediate vibrational states in the vicinity of the critical point, where the SDW order parameter changes dramatically, would then allow dynamical control over functional properties. Here we combine double photoexcitation with an X-ray free-electron laser (XFEL) probe to control and detect the lifetime and magnitude of the intermediate vibrational state near the critical point of the SDW in chromium. We apply Landau theory to identify the mechanism of control as a repeated partial quench and sub picosecond recovery of the SDW. Our results showcase the capabilities to influence and monitor quantum states by combining multiple optical photoexcitations with an XFEL probe. They open new avenues for manipulating and researching the behaviour of photoexcited states in charge and spin order systems near the critical point.

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